Márcio Dias Pereira

Maturação fisiológica de sementes de quaresmeira

The objective of this work was to study the maturation process of Tibouchina granulosa Cogn. seeds. Each inflorescence was identified in the day of its respective anthesis. Samples of fruits and seeds were collected weekly, and diameter, weight, color, moisture content and dry matter were determined. After seed extraction, analyzes were made for coloring, moisture content, dry matter, 1,000 seeds mass, speed and percentage of germination. Experimental design was carried out in a completely randomized block with four replications. Analysis of data obtained led to the following conclusions: seeds physiological maturity occurred 84 to 105 days, and seed harvest should be done between 84 to 98 days after the anthesis. The parameters which best characterized seed physiological maturity and the time for harvesting were moisture content and dry matter weight. The largest germination percentage was verified in extracted seeds from 77 until 105 days after the anthesis, and seeds vigor increased until 91 days. The size and color of fruits and seeds demonstrated efficiency as maturation parameters. Fruits initial dehiscences occurred after 105 days of the anthesis. Tibouchina granulosa presented seed dormancy after maturation.

Germinação de sementes de calabura (Muntingia calabura L.)

This work study was carried out to evaluate the effects of different flooding periods during germination and in the bean seeds vigor at UNOESTE Seed Analysis Laboratory. Seeds were submitted to flooding periods of 0, 8, 16, 24, 32, 40 and 48h at 25oC. Moisture content was taken before and after flooding periods. The germination test and physiological parameters, such as hypocotyl and root length and their dry weights, were obtained after periods of flooding. Results showed that germination and vigor decreased subsequently to flooding, germination decreased 55 percentage points after 8h of seed submersion. There were differentiation differences between among seed lots in germination tests after flooding periods equal to, or higher than 8h. Dead seed number and inhibition in hypocotyl and root development, shown in this work study, increased with the submersion time. In conclusion, eight hours of flooding cause irreversible damage to bean culture establishment, and the same periods of submersion, in the laboratory, could be a very good indicative to differentiate seed physiological quality.This work aimed to determine the best temperature, substrate and pre-treatment to subject to germinate Muntingia calabura L seed. The seeds were sowed in different substrates: on paper, among paper, on sand, among sand, on mixture soil + send + manure, among mixture soil + send + manure, on mixture soil + send + vermiculite and on vermiculite, incubated under constant temperature of 20, 25, 30oC and alternate of 20-30oC. The pre-treatment effect studied were the CaO and KNO3 on the mucilaginous seed germination. Experiments were undertaken following the completely randomized design with four replication of 25 seeds and the statistical analysis was performed by the factorial scheme. Primary root protrusion and even primary leaf emission was adopted as criteria to consider a germinated seed. Daily the germination was evaluated by determining percentages and germination velocity. It was found significative interaction between substrate and temperature. The best substrates were on sand and among sand under alternate temperature of 20-30oC, with 99 and 100% of germination, respectively. The pre-treatments CaO and KNO3, had better germination of mucilaginous seeds.

GERMINAÇÃO DE SEMENTES DE CUBIU EM DIFERENTES SUBSTRATOS E TEMPERATURAS 1

The cubiu (Solanum sessiliflorum Dunal) is a native arbustiva solanacea of the Amazon whose fruits present a high concentration citric acid. This study was carried to verify the effect of substrate and temperature on the germination capacity of cubiu seeds. This study was developed in the Seed Analysis Laboratories at the Agrarian Science Center at the Universidade Federal do Espirito Santo (CCA-UFES), Alegre-ES, Brazil. A cinpletely randomized design was used with four repetitions of 50 seeds, in a 6x6 factorial outline, with six substrates (on vermiculite (V); between sand (EA); on paper (SP); on sand (SA); on mixture soil+sand+esterco (TAE) and paper roll (RP) and six temperatures (constant of 20, 25 and 30oC and alternated of 20-25; 25-30 and 20-30oC). The following characteristics were assessed: germination (%); emergency speed index(IVE); hard and deteriorated seeds (%); normal and abnormal seedlings (%); seedlings height (mm) and canopy and root dry matter (mg). The results showed that the substrate on sand and between sand under 20-30oC were the best conditions for cubiu seed germination.

Testes de vigor para avaliação do potencial fisiológico de sementes de mamona (Ricinus communis L.)

A qualidade de sementes de mamona tem sido avaliada rotineiramente pelo teste de germinacao, cujos resultados, muitas vezes, nao sao confirmados em campo. Nesse contexto, os testes de vigor sao essenciais, pois retratam o comportamento das sementes sob maior amplitude de ambiente. Neste trabalho, objetivou-se avaliar a eficiencia de metodos para determinar o potencial fisiologico de sementes de mamona. Para tanto, foram utilizados sete lotes de sementes de mamona, cultivar AL-Guarany, apresentando teor de agua de aproximadamente 7% , que foram submetidos aos seguintes testes: germinacao, primeira contagem de germinacao, frio (a 10oC/7 dias e a 25oC/5 dias), porcentagem e velocidade de emergencia de plântulas, envelhecimento acelerado a 41oC e 45oC e 100% UR, por 48, 72 e 96 horas e condutividade eletrica (25 sementes embebidas em 75 e 100mL de agua destilada, a 25oC, por 2, 4, 6, 8, 24, 48 e 72 horas). Os testes de frio e de envelhecimento acelerado (41oC/72 horas e 100% UR) foram eficientes para avaliacao do potencial fisiologico de sementes de mamona, permitindo classificacao de lotes quanto ao vigor semelhante a emergencia de plântulas em solo. O teste de condutividade eletrica nao se mostrou adequado para avaliacao do potencial fisiologico das sementes de mamona.This work had the objective to determine the efficiency of different tests for the evaluation of physiological potential of castor bean seeds. Seven seed lots of AL-Guarany cultivar were submitted to the following tests: seed moisture content, standard germination, first count, cold test (10oC/7 days followed by germination at 25oC/5 days), seedling emergence, speed emergence index, accelerated aging (at 41oC and 45oC and 100% RH, for 48, 72, and 96h) and electrical conductivity (25 seeds soaked into 75 and 100mL of distilled water, at 25oC, for 2, 4, 6, 8, 24, 48, and 72 h). The trial was conducted in randomized completely design, with four replications. The means of treatments were compared by Tukey test at 5% probability. Results showed that cold test and accelerated aging (41oC/72 hours) were efficient to evaluate the physiological potential of castor bean seeds, allowing the classification of lots regarding vigor to be similar to the seedling emergence test. Electrical conductivity test was not adequate for the evaluation of physiological potential of these seeds.

Pre-germinative treatments in castor bean (Ricinus communis L.) seeds

Castor bean seeds have slow and irregular germination that frequently results in irregular seedling emergence in the field. This fact has been attributed to their probable impermeability to water. The objective of this study was to evaluate the effect of pre-germination treatments on seed performance. Five seed lots, AL-Guarany cultivar, were submitted to the following treatments: control (untreated seeds), scarification with sandpaper, caruncle removal, tegument removal, immersion in water for 12 and 24h, caruncle removal + immersion in water for 12 and 24h, scarification with sandpaper + immersion in water for 12 and 24h, germination at 10oC/7 days and at 25oC/5 days, germination at 10oC/7 days and at 30oC/5 days, accelerated aging at 41oC/48h and 100% RH. After each treatment, with exception of the germination at 10oC, the seeds were submitted to the germination test, at 25oC. Counts were performed at 7 and 14 days after sowing. In general, all the pre-germination treatments contributed to increasing the germination percentage of castor bean seeds in relation to the control. The most efficient treatments to speed up germination were scarification with sandpaper and caruncle or tegument removal. However, considering the practical application, scarification can be recommended to increase the percentage and speed of seed germination.

Germinação e vigor de sementes de cenoura osmocondicionadas em papel umedecido e solução aerada

The problems regarding carrot seeds performance in the field are constant justifying the use of techniques to accelerate germination and seedling emergence. The objective of this study was to evaluate the effects of two imbibition methods during priming on carrot seed germination and vigour.. Two seed lots of carrot, Brasilia cultivar, were primed in PEG 6000 -1.0 and -1.2MPa solutions for 4 and 8 days, at 20o C, using two imbibition methods: paper towel moistened with the respective solutions and immersion in aerated osmotic solutions. Non-primed seeds were used as control. The seeds were submitted to the following tests: germination, first count, percentage and speed of seedling emergence in the field at 10 and 25 days after sowing and primary root length. Priming in PEG 6000 for four days was effective in increasing the percentage and speed of germination and seedling emergence in the field. For primary root length, priming in PEG 6000 -1.2 MPa aerated solution was superior to moistened paper treatment.

ENVELHECIMENTO ACELERADO DE SEMENTES DE PINHÃO-MANSO

Jatropha curcas L. is an oleaginous plant that has distinguished itself by presenting the qualities necessary to the biodiesel production. This study aimed to adjust the accelerated aging test methodology to evaluate the physiological potential of Jatropha curcas seeds. For this, four seeds lots were initially characterized by water content, germination percentage and first counting, seedlings emergence percentage and speed index, low temperature germination, and shoot height. The treatments included three temperatures (41 oC , 42 oC , and 45oC) and four seeds exposure times (24, 48, 72, and 96 hours), in about 100% relative humidity. The accelerated aging test carried out for 24 hours, at 41oC, was efficient for evaluating the Jatropha curcas vigour seeds, allowing to classify lots according to vigour levels, similarly to the germination first counting tests, seedlings emergence, low temperature germination, emergence speed index, and shoots height.

Hydration of carrot seeds in relation to osmotic potential of solution and conditioning method

The objective of this study was to monitor carrot seed hydration in water and osmotic solutions to define appropriate conditions for priming treatment. Two Brasilia cultivar carrot seed lots were used. Seeds were imbibed in -1.0 and -1.2 MPa PEG 6000 osmotic solutions and in distilled water, in an incubator BOD at 20oC, using two different hydration methods: imbibition in moistened paper towel sheets and in aerated solutions. The imbibition curves for each seed lot were drawn after determining seed moisture content at 2, 4, 6, 8, 10, 12, 24, 48, 72, 96 hours hydration in water and after 2, 4, 6, 8, 10, 12, 24, 48, 72, 96, 120, 144, 168, 192, 216, 264, 312 hours hydration in PEG 6000 solutions. Seed hydration in distilled water was faster than in PEG 6000 solutions; the primary root protrusion occurred at 48 hours imbibition as seeds reached 54% moisture content. Osmotic conditioning of carrot seeds should be performed by imbibition in PEG 6000 -1.0 or -1.2 MPa solutions to attain 40% and 45% moisture content (moistened paper) or 40% and 45% (aerated solutions).

Vigor test for the evaluation of the physiology potencial of castor bean (Ricinus communis L.) seeds

A qualidade de sementes de mamona tem sido avaliada rotineiramente pelo teste de germinacao, cujos resultados, muitas vezes, nao sao confirmados em campo. Nesse contexto, os testes de vigor sao essenciais, pois retratam o comportamento das sementes sob maior amplitude de ambiente. Neste trabalho, objetivou-se avaliar a eficiencia de metodos para determinar o potencial fisiologico de sementes de mamona. Para tanto, foram utilizados sete lotes de sementes de mamona, cultivar AL-Guarany, apresentando teor de agua de aproximadamente 7% , que foram submetidos aos seguintes testes: germinacao, primeira contagem de germinacao, frio (a 10oC/7 dias e a 25oC/5 dias), porcentagem e velocidade de emergencia de plântulas, envelhecimento acelerado a 41oC e 45oC e 100% UR, por 48, 72 e 96 horas e condutividade eletrica (25 sementes embebidas em 75 e 100mL de agua destilada, a 25oC, por 2, 4, 6, 8, 24, 48 e 72 horas). Os testes de frio e de envelhecimento acelerado (41oC/72 horas e 100% UR) foram eficientes para avaliacao do potencial fisiologico de sementes de mamona, permitindo classificacao de lotes quanto ao vigor semelhante a emergencia de plântulas em solo. O teste de condutividade eletrica nao se mostrou adequado para avaliacao do potencial fisiologico das sementes de mamona.This work had the objective to determine the efficiency of different tests for the evaluation of physiological potential of castor bean seeds. Seven seed lots of AL-Guarany cultivar were submitted to the following tests: seed moisture content, standard germination, first count, cold test (10oC/7 days followed by germination at 25oC/5 days), seedling emergence, speed emergence index, accelerated aging (at 41oC and 45oC and 100% RH, for 48, 72, and 96h) and electrical conductivity (25 seeds soaked into 75 and 100mL of distilled water, at 25oC, for 2, 4, 6, 8, 24, 48, and 72 h). The trial was conducted in randomized completely design, with four replications. The means of treatments were compared by Tukey test at 5% probability. Results showed that cold test and accelerated aging (41oC/72 hours) were efficient to evaluate the physiological potential of castor bean seeds, allowing the classification of lots regarding vigor to be similar to the seedling emergence test. Electrical conductivity test was not adequate for the evaluation of physiological potential of these seeds.

Vigor test for the evaluation of the physiological potential of castor (Ricinus communis L.) seeds.

A qualidade de sementes de mamona tem sido avaliada rotineiramente pelo teste de germinacao, cujos resultados, muitas vezes, nao sao confirmados em campo. Nesse contexto, os testes de vigor sao essenciais, pois retratam o comportamento das sementes sob maior amplitude de ambiente. Neste trabalho, objetivou-se avaliar a eficiencia de metodos para determinar o potencial fisiologico de sementes de mamona. Para tanto, foram utilizados sete lotes de sementes de mamona, cultivar AL-Guarany, apresentando teor de agua de aproximadamente 7% , que foram submetidos aos seguintes testes: germinacao, primeira contagem de germinacao, frio (a 10oC/7 dias e a 25oC/5 dias), porcentagem e velocidade de emergencia de plântulas, envelhecimento acelerado a 41oC e 45oC e 100% UR, por 48, 72 e 96 horas e condutividade eletrica (25 sementes embebidas em 75 e 100mL de agua destilada, a 25oC, por 2, 4, 6, 8, 24, 48 e 72 horas). Os testes de frio e de envelhecimento acelerado (41oC/72 horas e 100% UR) foram eficientes para avaliacao do potencial fisiologico de sementes de mamona, permitindo classificacao de lotes quanto ao vigor semelhante a emergencia de plântulas em solo. O teste de condutividade eletrica nao se mostrou adequado para avaliacao do potencial fisiologico das sementes de mamona.This work had the objective to determine the efficiency of different tests for the evaluation of physiological potential of castor bean seeds. Seven seed lots of AL-Guarany cultivar were submitted to the following tests: seed moisture content, standard germination, first count, cold test (10oC/7 days followed by germination at 25oC/5 days), seedling emergence, speed emergence index, accelerated aging (at 41oC and 45oC and 100% RH, for 48, 72, and 96h) and electrical conductivity (25 seeds soaked into 75 and 100mL of distilled water, at 25oC, for 2, 4, 6, 8, 24, 48, and 72 h). The trial was conducted in randomized completely design, with four replications. The means of treatments were compared by Tukey test at 5% probability. Results showed that cold test and accelerated aging (41oC/72 hours) were efficient to evaluate the physiological potential of castor bean seeds, allowing the classification of lots regarding vigor to be similar to the seedling emergence test. Electrical conductivity test was not adequate for the evaluation of physiological potential of these seeds.